Process of leaching ores.



J. A. M cCASKELL.

PROCESS OF LEACHING ORES. APPLICATION FILED JUNE 2, 1914.

Patented May 4, 1915.

source A a ecrz'v'c Carrenf'h JASPER A. MOGASKELL, OF SALT LAKE CITY, UTAH.

PROCESS OF LEACHING ORES.

Specification of Letters Patent.

Patented May 4, 1915.

Application filed June 2, 1914. Serial No. 842,426.

To all whom it mag concern Be it known that I, J ASPER A. MoCAsKnLL, a citizen of the United States, residing at Salt Lake City, in the county of Salt Lake and State of Utah, have inventedcertain,

leaching gold, silver, and copper ores and then regenerating the solvent.

A leading object of my invention is to produce chlorin gas electrolytically from 'metallic chlorids (sodium chlorid preferred), and to use the chlorin thus produced to chlorinate the metals in the ore that is being treated. An aqueous solution of these chlorids is subsequently electrolyzed in the cathode side of a diaphragmed electrolytic cell, resulting in the regeneration of the original chlorid solution (sodium chlorid) and the depositing of the metals in solution on the cathode.

With the above and other objects in View my invention consists of the process which I will hereinafter describe and claim.

In the accompanying drawings I have shown one type of apparatus which is adapted for ,the carrying out of my process and wherein I Figure 1 represents a side elevation of one type of apparatus suitable for carrying out my invention, certain of the parts being shown in section. Fig. 2 is a sectional view of an electrolytic cell showing the diaphragm interposed between the anode and cathode compartments thereof.

While I have shown one type of apparatus for carrying out my process I wish it understood that I do not limit the process to this particular apparatus, but claim. the

right to use the sallent steps of the process in any arrangement or apparatus where the same may be used to produce the desired results.

In the apparatus shown, A, represents an agitatingtank of suitable construction in Y which the ore is designed to be agitated in the presence of chlorin, the ore being admitted to the tank from a suitable reservoir or bin, A, which delivers the ore to an,

ciated with the grinding apparatus isa storage tank, B, initially containing water, which tank, after the first cycle in the operation will contain the spent liquors from the anode compartment of the electrolytic cells, as I will hereinafter describe, said tank having a delivery pipe, B, leading the fluid contents of the tank for admixture with the ore being reduced in the grinding apparatus.

A suitable tank or holder, F, is adapted to contain chlorin and a pipe F from this tank leads into the bottom of a vertical column, a, located within the agitating tank, A, whereby the chlorin is introduced into the bottom of the column under pressure and acts as the active agent for agitating the contents of said tank, and which contents comprise the crushed ore. saturated with the water, or spent liquors from the anode compartment of the electrolytic cells, as before explained. The chlorin storage tank, F, is provided with a pipe, L, which leads from the upper part of this tank into the top or upper portion of theEagitating tank, and a pipe, K, also connects the tank, F, with the anode compartment of the electrolytic cell, there being a suitable pump, 10, introduced into the length of this pipe for delivering the chlorin gas from said anode compartment back into the storage tank, F.

The electrolytic cells, D, D, D are each composedo'f suitable material and have any desired capacity and they are each provided with an impervious partition or diaphragm stantially as a bi-polar electrode, sald dlap'hragm forming at'one side thereof, the cathode compartment and at the other slde the anode compartment, the first-named compartment being provided with a suitable cathode, 13, and the second compartment having an anode, 14, said anodes and cathodes; being electrolytically connected to a generator, 15, or .suitable source of electric current;

In the aforesaid drawing I have shown for illustrative purposes, three electrolyt1c cells, with the anode compartment of one cell connected to the cathode compartment of an adjacent cell. by suitable -valve-controlled pipes, I, which connect with the bottom of the aforesaid compartments.

H represents a storage tank for an anolyte consisting of water containing a small percentage of metal chlorids and which anolyte is conducted to the tank through a pipe, G,

, 12, which is designed to act sub- 5 for the carrying out of my and from the tank it is pumped through a suitable pipe, H, to the storage tank, -B, before mentioned. I j

The agitating tank, A, has a'bottom dis- 5 charge which is appropriately connected to a filter press, C, of any 'suitable character and which is herein shown as being set at an incline, this press containing an interior carriage, C, with filter frames, C and sald carriage being adapted to be run 1n and out of the tank in a manner Wellknown in the metallurgical art, the metal chlorid solution from this filter press being delivered through a pipe, E, to a pump, E, and

thence forced into the cathode compartment "of the electrolytic cells through suitable branch pipes, E as shown.

As before stated, each of the electrolytic cells is divided into a cathode and anode o compartment by means of. an impervious diaphragm, 12, which serves as a bi-polar electrode as hereinafter explained. One form of this diaphragm is shown in Fig. 2, as being composed of two sheets of asbestos board, 6,- b, cloth, or porous earthen-ware 'or similar material of a porous character, and between the adjacent surfaces of said sheets, and thereby rendering the diaphragm impervious is placed a thin film of mercury,

3 c, the thiclmess of which is, preferably, just 0 out my process I do not limit the same to the-use of this particular diaphragm or bipolar electrode. In the drawings I have shown the diaphragm or bi-polar electrode as vertically disposed, but I do not confine 5 myself to this arrangement as it is quite apparent that the same result will be obtained if the diaphragm or 'bi-polar electrode is horizontal and divides the electrolytic cells into the anode and cathode compartment-s 5 before mentioned.

- In order to make the steps of my process sufficiently clear for those skilled in t e art to work the same I' will now describe the cycleof operation in treating ore. Thevore is first ground to a suitable size, say from twelve to two hundred mesh, depending upon the character of the ore treated. This ground or slimy ore is delivered to the leaching or agitating tank, A, where the co ore is a 'tated in the presence of chlorin delivere from the tank, F, in which tank the chlorin gas is stored under ressure and is delivered into th ottom o the central column, a, in the itatin tank, as before as mentioned. It will thus e seen that the dium chlorid is added to the water used in crushing the ore and delivered from the tank, B, when first starting the operation. After the first cycle, the tank, B, will contain the spent liquors from the anode compartment of the electrolytic cells, which are derived from the tank, H, and pumped back to the tank, B, as shown. After the ore is thoroughly chlorinated in the tank, A, it is run into the filter press and the clear water 0 filtrate obtained from the filter medium with which the press is supplied, is pumped through the pipe, E, to the cathode compartment of the electrolytic cells, D, D, D This filtrate contains the chlorid of gold, 35 silver, copper, &c., in solution. The solution of sodium chlorid and the extracted metallic chlorids is admitted into the oathode compartment where the electric current dissociates the metallic chlorids into the metals which collect at the cathode, 13, and chlorin which tends to collect at one side of the mercury diaphragm, 12, the mercury diaphragm, of course, behaving as a bipolar electrode. The sodium chlorid will 5 also be somewhat dissociated in the cathode compartment, the sodium being deposited at the cathode, 13, where it will unite with water to form sodium hydrate and hydro- I gen; the chlorin will tend to collect adjacent to one side of the mercury diaphragm. The solution in the anode compartment will contain but little metallic chlorids in solution but considerable sodium chlorid which will be dissociated into chlorin which will collect .at the anode, 14, and finally be delivered through the pipe, K, to the chlorin tank, F, and sodium will collect at one side of the mercury diaphragm where it will amalgamate with the mercury in the diaphragm. The sodium in the amalgam will then come into contact with the chlorin which has been liberated into the cathode compartment and form sodium chlorid, thus regenerating the original solvent agent.

From the foregoing it will be understood that my process is thus made continuous "by the regeneration of the original saturated. sodium chlorid solution that I started with as an anolyte. Theoretically, there should be 120 -no loss of'chlorin during the cycle, but there .always is a certain mechanical loss that is tobe made up by adding more salt to the solution, or in other words standardizing the catholyte solution before it is sent on emu- 5 other cycle of operation.

In large installations, the sheets, I), b, of

asbestos or like material between which the film of mercury, c, is contained, are rigidly .held in place between the perforated grids,

boards or frames, but I do not confine myself to the exclusive use of asbestos, as I have used certain kinds of heavy canvas -with success, and doubtless other material of a more or less porous character may be used as a substitute for the asbestos. The amount of mercury used is very small as the asbestos boards, or their equivalent are placed in close relation, just so they do not touch is all that is required. In practice, I have used the anode and cathode compartments of the electrolytic cells is important in the working out of the complete process, and that as a result of my process I produce chlorin gas electrolytically from metallic chlorids and use the chlorin thus produced to chlorinate the metals in the ore that is being treated. The anode and cathode which I employ may be of any suitable character; for instance the anode may be composed of iron, carbon, &c., and the cathode may be carbon, iron, copper, &c., as is found suitable.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is 1. The process herein described of leaching ores consisting, essentially, in producing chlorin gas electrolytically from metallic chlorids and using the chlorin thus produced to chlorinate the metals in the ore that is being treated, and regenerating the solvent by electrolyzing an aqueous solution of the chlorids in the cathode side of an electrolytic cell.

2. The process herein described of leaching ores and then regenerating the solvent, said process consisting, essentially, in producing chlorin gas electrolytically from metallic sodium chlorids, using the chlorin thus produced to chlorinate the metals in the ore that is being treated, and subsequently electrolyzing an aqueous solution of the chlorids in the cathode side of an electrolytic cell, thereby regenerating the original sodium chlorid, the metals in solution being deposited on the cathode of said cell.

3. The process herein described of leaching ores consisting, essentially, in producing chlorin gas electrolytically from metallic chlorids and delivering the chlorin thus produced under pressure into the body of the ore being treated for the purpose of both agitating and chlorinating the metal contents of said ore, and subsequently electrolyzing an aqueous solution of the chlorids in the cathode side of an electrolytic cell and regenerating the original chlorid solution thereby.

at. The process herein described of leaching ores, which consists, essentially, in producing chlorin gas electrolytically from metallic chlorids; utilizing the chlorin thus produced to agitate and chlorinate the metals in the ore that is being treated; filtering the ore and separating the liquid filtrate containing the metal in solution, and delivering said filtrate to the cathode side of an electrolytic cell; supplying the anode.

compartment of said cell with a saturated solution of a metallic chlorid; separating the compartments of the cell by a layer of mercury; electrolyzing the cell; and storing the chlorin produced in the anode compartment of the cell and utilizing the same for chlorinating the metals in a fresh charge of ore.

5. The process herein described of leaching ores which consists, essentially, in producing chlorin gas electrolytically from metallic chlorids; utilizing the chlorin thus produced to agitate and chlorinate the metals in the ore that is beingtreated; filtering the ore and separating the liquid filtrate containing the metals in solution and delivering said filtrate to the cathode side of an electrolytic cell; supplying the anode compartment of said cell with a saturated solution of a metallic chlorid; separating the compartvments of the cell by a layer of mercury;

electrolyzing the cell; and delivering the sodium derived from the splitting up of the chlorid in the cell, through the body of mercury so that it acts as a soluble anode which combines with the chlorin that is liberated at the cathode; and utilizing the resulting anolyte containing a small percentage of metal chlorids, for saturating a fresh charge of ore. In testimony whereof I aflix my signature in presence of two witnesses.

- JASPER A. McGASKELL. Witnesses:

HARRY L. RoBERTs, G. F. SUMMERS. 

